Help! 20inch rear kit

[Monkey Tennis]

Hi im looking for a cheap second hand kit for my bike its a 110mm on the dropouts or just any help on the cheapest one available, not bothered about battery I'll sort that later. Thanks

 

[vfr400]

110mm is narrower than a standard rear motor. They're all 135mm or 150mm. Front motors are 100mm or 85mm. Another thing is that you need a high-speed motor for 20" wheels otherwise you'll be stuck with 12mph on a good day, though it'll winch you up any hill.

 

[Monkey Tennis]

Thankyou very much, i didnt realise that at all, Thats massive help, could you suggest what would be a good combination and voltage etc? Thankyou again

 

[Woosh]

you should post pictures of the donor bike. It'll help to figure out what's best.
Most folding bikes are dangerous to ride at high speed, cars don't expect to see you on the main roads, potholes are also more dangerous to smaller 20" wheels and suspension forks on folding bikes are rare and when they are fitted, give poor performance.
That's why many electric folding bikes have their speed optimised around 12-13mph.

 

[vfr400]

I think your best chance of electrifying that bike is with some sort of chain-drive system or, if your bottom bracket is standard, you could use a crank-drive. You'll be lucky to get either of those second hand. Do you know if your bottom bracket is standard 68mm one with standard threads? It looks like yours is a one-piece crank, in which case crank-drives are out unless you can make some sort of adapters.

 

[Monkey Tennis]

I'ts this I'm trying to convert, 120mm rear 100mm front